According to The Free Press of Mankato, Captain Kris Markeson of the Waseca Police Department told reporters that authorities believe the youth was acting alone. He says he believes the teen would have succeeded if he had not been caught.

A visibly shaken Markeson said he was disturbed by the amount of guns and other material the youth obtained. He said he can’t divulge if specific students were targeted.

The investigation began after three small explosive devices were discovered at a playground in late March.